While the phrase, "praying in tongues" (or closely similar) does not appear, it is reasonable to conclude that is what Paul was referring to in 1 Corinthians 14:14-15, and what Jude meant in v. 20.
It would seem the Jude reference in the previous verse 19 is speaking of those sensual ones who require a sign to confirm something.
In order to build our selves up in the faith we must exercise it by making our request known called praying in the Spirit as it leads us. .
The Psalms are a good example of praying in the Holy faith of God, as David by the faith of Christ was moved to do so. .
The reference in 1 Corinthians 14 was altered the word unknown was added. That portion is still under the idea of two people understanding each other .Like at Pentecost when each heard the other in their own language.
14 For if I pray in an unknown tongue, my spirit prayeth, but my understanding is unfruitful.
15 What is it then? I will pray with the spirit, and I will pray with the understanding also: I will sing with the spirit, and I will sing with the understanding also.
There's this verse also...
2 Corinthians 11:4 KJV
"For if he that cometh preacheth another Jesus, whom we have not preached, or if ye receive another spirit, which ye have not received, or another gospel, which ye have not accepted, ye might well bear with him."
That's a verse where the Apostle who said " I thank my God, I speak with tongues more than ye all:" was talking to people whom he had just been teaching how and when to use tongues(and when not to)... was warning them NOT to fall for a change in gospel, change in Jesus, or change in SPIRIT than what has been poured out so far.
The spirit so far had been arriving with speaking in tongues.
And it can't even be claimed that "tongues had ceased because the bible was finished" because 2 Corinthians is NOT the end of the bible.
Love in Jesus,
Kelby
Tongues would first have to be defined as to what it is and what was the purpose for God changing the manner from Hebrew to all the languages of the world ?
The doctrine did not fall from the thin air one day. It would seem those who require a sign before they believe have no roots for their idea .It is like they saw a verse and built a new oral tradition of men . Which is this case clearly makes the word of God without effect.
The sign cannot confirm unbelief and belief at the same time. It would be like a sign that said "Chicago 250 mile ahead thanks for visiting you have just left the Chicago city limits".
The Spirit is always involved in bringing prophecy .No matter which "manner" to includes tongues as one of the many manners that God did bring new revelations when the possibility to add was still available..
Prophecy is not of men . And the sign confirms unbelief to begin with. Back to the foundation of the doctrine. Isaiah 28 Once the sign is confirmed as to what it represent then the rest of the doctrine will fall into place. Ignore the foundation then a parson might as well ignore the outcome.